I recently picked up a 1993 Dodge D150 Long bed with the 5.2 v8 engine. I have had a pretty big issue since I bought the truck. As I'm driving, it gets up to speed, then the engine feels like it bogs down, I feel a jerking motion and then the engine returns to normal with full power. At first I thought it was transmission because I couldn't tell if the engine was actually bogging down (I don't have a tach) and it felt like one hard jerk as if it was trying to get into gear. I got a new transmission put in, and the issue is still there. The issue got slightly worse and I was able to determine it feels like a fuel issue. Me and my dad changed sparkplugs, distributor and rotor, fuel filter, fuel pump, TPS and the issue is still there. I took it to a shop and they did not know what was wrong with it. He agreed it was a fuel issue. They inspected the fuel regulator cleaned the injectors, and changed the fuel pump (again). They noticed that the sparkplugs were already fouled around the edges. The past two mornings, the truck has had a hard time starting and when it does start, any gas pedal makes the truck stall out. After a while, I can start to drive the truck, but it takes some playing with. Again, I feel like it is a fuel issue. I bought this truck so that if my other car (or any of my friends cars) break down, I can hook up a car trailer and pull it, but I do not feel comfortable doing that in it's current state, even while it's running good (the issue comes and goes, some days if runs flawlessly, other days it is almost undrivable). My other car is currently also not working so I am daily-ing this truck. Any help would be appreciated.

 

Do you have a scanner that can read live data? I would be tempted to have a look at what the various sensors are telling the PCM when it is screwing up. Might be as simple as a coolant temp sensor. (keep in mind, you should have two, a one-wire for the gauge in the dash, and a two-wire for the PCM.)

 

Unfortunately, I do not. The truck has an OBD1 port and I have yet to find a scanner that looks like it would work
I have some ideas as to what it could be, but the cost of this project is quickly adding up

 

Yeah, the OBDI stuff is getting REALLY hard to find. Snap On MT2500, with the right cartridges would do the trick. They are frequently on EBay, but, are generally around 400 bucks or so.

 

Is the check engine light on? If so you can see what that is with the key dance.
https://www.allpar.com/threads/the-1...ost-1085223107

 

No check engine light. I did some googling and found the codes the computer gives: 12 (battery was recently disconnected) and 55 (no more codes to read), both of which arent important. Leaves me in the dark. I still believe it's a fuel issue, however I am trying to think outside the box. It feels like it could be a lot of different things. When I had the new transmission put in, I was told there was a bad fuel line they replaced. I wonder if possibly another line is bad and is sucking air? It's the only other thing I can think of with the fuel system. When I bought the truck, the guy I bought it from blamed the O2 sensor for the issue. I have yet to change it but I wouldn't imagine that is the issue, especially not having any codes (would give a 21) but I am replacing it today anyways. I do not have a way to get live diagnostic data. Any other ideas I could throw at this thing? It is my daily driver so it is scary to see it dying out.

 

Replacing the O2 sensor might help, but, if you experience the problem at cold startup, at that point, the O2 sensor isn't doing anything.

Your fuel system runs right about 39-40 PSI, so, some rubber hose and a couple clamps are NOT fix for a bad line. That's a recipe for disaster. If that's what they did, fix it properly RIGHT AWAY.

Might try cleaning the throttle body really well..... Actually take it off the truck, and clean it out. Pay special attention to the IAC well. They like to fill up with crap, and you get some odd behavior.

What plugs are in it? How old are the plug wires?

The problem you run into here is, there are a LOT of different things that can cause your symptoms. Without being able to see live data, (what the PCM sees is going on) all we can do is guess, and that can get expensive in a hurry.

 

https://www.obdadvisor.com/obd1-scanner-review/